The present invention is directed to an improved furnace design, specifically to an air delivery and burner system which extends across the top of a furnace used for the catalytic steam reforming of hydrocarbons.
Previous designs for catalytic steam reforming furnaces used brick to form the top of the radiant section of such a furnace. In addition to the conventional arch steel, the brick required steel suspensions for support. Further, previous designs employing air preheat generally utilized overhead ducting, with take-offs to each burner, resulting in a hot and noisy penthouse above the brick floor, i.e. the top of the radiant section of the furnace. This design resulted in a congested, noisy, and hot area above the radiant section of the furnace. Further, coupled with this congestion and heat at the operator level, a personnel hazard existed in the event of mechanical failure of the bricks resulting in high temperature openings in the arch, flash back of flames through the burner intake ports and/or loss of draft causing hot gases generally to rise by convection through the arch.
A catalytic steam reforming furnace of previous design is disclosed in U.S. Pat. No. 3,257,172.